Disgraced former road pro Lance Armstrong is beginning to lose support among key allies in the wake of last week's report by USADA (United States Anti-Doping Agency) that provides extensive details of a doping conspiracy.

One of his oldest and staunchist supporters, sporting goods manufacturer Nike, has just announced it is severing ties with him, and Armstrong's cancer-fighting charity - Livestrong - released a statement that he would step down as Chairman of the Board of Directors.

This is a significant move by Nike, who has in the past stood by embattled athletes, such as Tiger Woods, Kobe Bryant and Michael Vick. The Nike statement said that company was severing ties "due to the seemingly insurmountable evidence that Lance Armstrong participated in doping and misled Nike for more than a decade."

Nike was also reportedly accused by Greg Lemond's wife Kathy Lemond of paying Hein Verbruggen (former UCI President) $500,000 for covering up a drug test, and a group of cyclists yesterday protested Nike's continued support of Armstrong.

However, Nike will remain as a supporter of Livestrong.

The Livestrong charity almost simultaneously issued a statement on their website ( livestrong.org ) that Armstrong would step down, citing the ongoing controversy.

In the release, Armstrong was quoted: "I have had the great honor of serving as this foundation's chairman for the last five years and its mission and success are my top priorities. Today therefore, to spare the foundation any negative effects as a result of controversy surrounding my cycling career, I will conclude my chairmanship."

"My duties will transfer to Vice Chairman Jeff Garvey who will serve as chairman. Jeff's guidance and wisdom have been critical to shaping the foundation’s work since its earliest days. Jeff was this organization's founding chairman and I have full confidence that under his leadership, the foundation will continue expanding its ability to serve cancer survivors."

So far, there has been no word from Armstrong's other sponsors, such as Anheuser-Busch, Oakley and Trek Bicycles.